**7.2 While interpreting OGTT result you will not get information concerning**

a. Patient preparation for and how the glucose was administrated.

b. The result shows assessment of glucose tolerance at the time of the test only and cannot provide any other information.

2.Usually no glucosuria during fasting but mainly post-prandial

*Oral Glucose Tolerance Test (OGTT): Undeniably the First Choice Investigation…*

diabetes

*DOI: http://dx.doi.org/10.5772/intechopen.96549*

intestine is efficient in glucose absorption.

a. Diagnosed diabetes mellitus b. Suspected Type 1 DM c. Unconscious patient

**Table 6.**

**129**

d. Patient who can not obey instructions e. Refusal to follow instructions

f. Not for diabetes follow-up except during treatment of secondary diabetes; eg acromegaly, glucagonoma, Cushing's syndrome, Phaeochromocytoma

g. Hospitalized, acutely ill or immobile patients

emptying.

3. It may be physiological, in pregnancy or in renal disease or early

e. A flat glucose tolerance curve can be a normal finding and is as a result of rapid metabolism and not of either deficient absorption or slow gastric

Under certain pathological conditions such as hyper- and hypothyroidism changes in the gastric emptying rate may significantly alter the shape of the glucose tolerance curves [79]. Rapid gastric emptying associated with duodenal ulcer and partial gastrectomy where plasma glucose rises rapidly within 30 minutes of glucose ingestion stimulating hyperinsulinaemia and resultant reactive hypoglycaemia though measurement of serum insulin levels does not reveal evidence of such direct relationship. In a healthy young adult with increase physiologic activities, there is associated rapid metabolism and when venous rather than capillary blood is analyzed, a flat curve can be a normal findings and not of either deficient absorption or slow gastric emptying. Hypoglycaemia in a fasting subject is normally prevented by hepatic gluconeogenesis. This stopped after glucose ingestion when blood glucose rises, and begun when plasma glucose is falling preventing fasting hypoglycaemia Reactive hypoglycaemia in either normal healthy young adult, patient with peptic ulcer or partial gastrectomy might, therefore, be due to the failure of the liver to resume glucose production sufficiently and rapidly. The normal exponential pattern of gastric emptying results in a very gradual decline of the rate at which glucose enters the intestine and this should provide ideal conditions for the liver gradually to resume glucose production. The absorption of glucose by the small intestine is highly efficient. After ingestion of a concentrated solution, a combination of slow gastric emptying, dilution within the duodenum, and active peristalsis ensure that within the jejunum the glucose solution no longer remains hypertonic. The small

Every dynamic test requiring appropriate patient preparation and procedure for the conduct of the test will not be without contraindication if result is to be reliable. Such contraindications for conduct of OGTT are shown in **Table 6**. The primary objective is to demonstrate presence of dysglycaemia in a condition that has long latent period, except when monitoring success of treatment in secondary causes of hyperglycaemia. Subject must be conscious and alert to obey order (in both preparation and conduct of the test), in a no stressful condition, physically or otherwise. Patient should be able to take the stated amount or an equivalent and under influence of no other condition except what is being investigated for.

solution

*Conditions under which OGTT should not be conducted or when procedure should be stopped.*

h. Vomiting during the procedure

i Patient who could not consumed the glucose

j. Patient who developed moderate to severe hypoglycaemia during the test k. Do not perform the test on patients with uncontrolled thyroid dysfunction, under physical stress, eg post surgery, trauma, infection or extreme psychological stress or in patient with hypokalaemic periodic paralysis


Therefore result will be better interpreted with the cognition of the above in mind.
